Boardingkortet er klar.

Boardingkortet is the noun boardingkort with the definite ending attached.

• boardingkort = boarding pass
• boardingkortet = the boarding pass

In Danish, the definite article is often added to the end of the noun instead of being a separate word before it.

Because boardingkort is a neuter noun, its definite singular form takes -et:

• et boardingkort = a boarding pass
• boardingkortet = the boarding pass

Also, boardingkort is a compound noun:

• boarding
  • kort

The last part, kort, determines the gender, so the whole word is neuter.

Danish usually puts the at the end of the noun as a suffix.

So instead of saying something like a separate the boarding pass, Danish normally says:

• boardingkortet

This is very common in Danish:

• en bil = a car
• bilen = the car
• et hus = a house
• huset = the house

A separate definite word can appear in some other structures, especially when there is an adjective before the noun:

• det klare boardingkort = the ready/clear boarding pass

But in your sentence, there is no adjective inside the noun phrase, so the attached definite ending is the normal form.

Er is the present tense of at være, which means to be.

So:

• jeg er = I am
• du er = you are
• det er = it is

Danish does not change the present-tense form of to be depending on the subject the way English does with am / is / are. The form is just er for all persons.

In this sentence, er links the subject boardingkortet to the description klar.

This is an excellent question, because many learners would notice this.

In standard Danish, many speakers and teachers would expect:

• Boardingkortet er klart.

Why? Because boardingkort is a neuter noun (et boardingkort), and predicative adjectives usually agree with neuter singular nouns:

• Bogen er klar. = The book is ready/clear.
  (bog is common gender)
• Svareret er klart. = The answer is clear.
  (svar is neuter)

So with boardingkortet, standard agreement would normally be:

• klart

If you saw Boardingkortet er klar, it may be:

• a mistake,
• a nonstandard form,
• or simply a sentence written without strict attention to adjective agreement.

For learning purposes, the safest standard version is:

• Boardingkortet er klart.

Here, klar usually means something like:

• ready
• available
• prepared
• sometimes finished

In travel or airport contexts, klar often means that something is now ready for use or has been processed.

So the idea is that the boarding pass is now available or ready.

Be aware that klar can mean slightly different things depending on context:

• Maden er klar. = The food is ready.
• Er du klar? = Are you ready?
• Det er klart. = That is clear / obvious.

The structure is:

• Boardingkortet = subject
• er = verb
• klar / klart = subject complement

So the pattern is:

• Subject + verb + complement

This is a very common Danish sentence pattern, and in a simple main clause like this, it looks quite similar to English.

Danish main clauses also follow the verb-second rule. That means the finite verb usually comes in the second position.

For example:

• Boardingkortet er klart.
• Nu er boardingkortet klart.

In the second example, Nu comes first, so er still stays in second position.

Yes. It is a normal Danish travel word, even though part of it comes from English.

Danish often uses loanwords and international travel vocabulary. Boarding is borrowed, and kort is a native Danish word meaning card or pass.

So boardingkort is a standard compound noun in Danish, even if it looks partly English.

Here are the most useful forms:

• et boardingkort = a boarding pass
• boardingkortet = the boarding pass
• boardingkort = boarding passes or boarding pass in some indefinite contexts, depending on structure
• boardingkortene = the boarding passes

With the adjective, standard agreement would be:

• Et boardingkort er klart. = A boarding pass is ready.
• Boardingkortet er klart. = The boarding pass is ready.
• Boardingkortene er klare. = The boarding passes are ready.

Notice the adjective changes:

• klar for common gender singular
• klart for neuter singular
• klare for plural

You would usually say:

• Mit boardingkort er klart.

Here is what changed:

• mit = my for a neuter singular noun
• boardingkort is still neuter
• klart matches the neuter noun in standard Danish

Compare:

• min billet = my ticket
• mit boardingkort = my boarding pass

This is a useful pattern to learn, because Danish possessives also depend on the gender and number of the noun.